What was clearly a burgeoning trend officially became all the rage in baseball this week. With Justin Verlander, Buster Posey and Adam Wainwright agreeing to new contracts that will keep them with their current teams long after they would have been eligible for free agency, there's no doubt the age of teams retaining their stars is upon us.

There will continue to be exceptions, of course. Zack Greinke and Josh Hamilton changed teams this winter, Albert Pujols and Prince Fielder the year before. Robinson Cano has yet to ink a new deal done with the Yankees. But the list of players who have chosen to forgo free agency was already long, and it keeps getting longer.

Before Verlander, Posey and Wainwright, it was Felix Hernandez, Joey Votto, and Cole Hamels. Evan Longoria and Matt Kemp agreed to massive deals to stay where they are, as well.

If you're looking for one reason why the highest-revenue teams seem a little less dominant these days, this is it: Middle-class teams have the money to keep the stars they draft and develop, so those players don't hit free agency. Or if they do, it's not until well after their prime years.

In each case, of course, there are unique circumstances. The Rays lock up their young players when they can, out of necessity -- they know they can't really compete for top-dollar free agents. The Phillies had the money to keep Hamels, so they did. The Tigers, though not traditionally one of baseball's biggest-spending clubs, are clearly in win-now mode. And the Cardinals had flexibility after losing Pujols -- but also urgency.

"We are trying to make sure that we retain our top talent that we know we can count on to be a part of the organization," St. Louis general manager John Mozeliak said. "In other words, a no-flight risk. Then we believe in what our system is going to produce to augment that."

Underlying all of it, though, is money -- of course. More cash is becoming available to clubs through both local and national television contracts. And it becomes somewhat cyclical. As fewer stars hit free agency, clubs have fewer places to spend that money. So they spend it on their own players, and the cycle continues.

"I see clubs doing a better job of, when they get a talent, keeping the talent," Nationals general manager Mike Rizzo said recently.

It's also easier for a club to be confident in re-signing its own player. The team knows the player's makeup and medical history. The front office knows how he fits in with what they already have. Every big contract is a risk, but a big contract with your own player feels like less of a risk than a big contract with a player who has never been in your organization before.

Then there's the players' side. In many of these cases, the deals are getting done a year, two years, even three years before the players are eligible to test the market. They don't know what their careers will do in those intervening years. Players get hurt. They have bad years.

While an agent might be able to look rationally at the situation and say that, yes, the best way to maximize your value is to go to the open market, it may not look the same way to a player. When life-changing money is on the table, right now, it can be extremely difficult to turn down.

The players might, in some cases, be able to make more money if they were to head to the open market, but it's not guaranteed. And so you get Posey staying in San Francisco, Votto staying in Cincinnati, Verlander continuing to wear the old English 'D.'